Afloat dream meaning is explained below using 3 different sources. Each interpretation is shown with its source.

Interpretation 1 — Stearn Robinson - Tom Corbett

The meaning of this dream depends on its aspect If the water was calm and clear, a happy event is in view; if the water was rough or murky, you will be called on to cope with some difficulties not of your own making.

See also Water, Ocean, River, Ship, Drown, etc.

Source: The Complete Guide to Interpreting Your Dreams Author: Stearn Robinson - Tom Corbett

Interpretation 2 — Silvana Amar

The meaning of this dream depends on its aspect.

If the water was calm and clear, a happy event is in view; if the water was rough or murky, you will be called on to cope with some difficulties not of your own making. 

Source: The Bedside Dream Dictionary Author: Silvana Amar

Interpretation 3 — Internet Archive - Anonymous

On smooth water, a happy destiny is in view; on a rough sea, troubles not of your own making.
Source: Mystic Dream Book Author: Internet Archive - Anonymous